content: /**
   * Copyright (c) 2016-present, RxJava Contributors.
   *
   * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in
   * compliance with the License. You may obtain a copy of the License at
   *
   * http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software distributed under the License is
   * distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See
   * the License for the specific language governing permissions and limitations under the License.
   */
  
  package io.reactivex.observable.internal.operators;
  
  import static org.junit.Assert.*;
  
  import java.util.*;
  
  import org.junit.Test;
  
  import io.reactivex.common.*;
  import io.reactivex.common.exceptions.TestException;
  import io.reactivex.common.functions.Function;
  import io.reactivex.observable.*;
  import io.reactivex.observable.Observable;
  import io.reactivex.observable.Observer;
  import io.reactivex.observable.subjects.PublishSubject;
  
  public class ObservableElementAtTest {
  
      @Test
      public void testElementAtObservable() {
          assertEquals(2, Observable.fromArray(1, 2).elementAt(1).toObservable().blockingSingle()
                  .intValue());
      }
  
      @Test
      public void testElementAtWithIndexOutOfBoundsObservable() {
          assertEquals(-99, Observable.fromArray(1, 2).elementAt(2).toObservable().blockingSingle(-99).intValue());
      }
  
      @Test
      public void testElementAtOrDefaultObservable() {
          assertEquals(2, Observable.fromArray(1, 2).elementAt(1, 0).toObservable().blockingSingle().intValue());
      }
  
      @Test
      public void testElementAtOrDefaultWithIndexOutOfBoundsObservable() {
          assertEquals(0, Observable.fromArray(1, 2).elementAt(2, 0).toObservable().blockingSingle().intValue());
      }
  
      @Test
      public void testElementAt() {
          assertEquals(2, Observable.fromArray(1, 2).elementAt(1).blockingGet()
                  .intValue());
      }
  
      @Test(expected = IndexOutOfBoundsException.class)
      public void testElementAtWithMinusIndex() {
          Observable.fromArray(1, 2).elementAt(-1);
      }
  
      @Test
      public void testElementAtWithIndexOutOfBounds() {
          assertNull(Observable.fromArray(1, 2).elementAt(2).blockingGet());
      }
  
      @Test
      public void testElementAtOrDefault() {
          assertEquals(2, Observable.fromArray(1, 2).elementAt(1, 0).blockingGet().intValue());
      }
  
      @Test
      public void testElementAtOrDefaultWithIndexOutOfBounds() {
          assertEquals(0, Observable.fromArray(1, 2).elementAt(2, 0).blockingGet().intValue());
      }
  
      @Test(expected = IndexOutOfBoundsException.class)
      public void testElementAtOrDefaultWithMinusIndex() {
          Observable.fromArray(1, 2).elementAt(-1, 0);
      }
  
      @Test(expected = IndexOutOfBoundsException.class)
      public void elementAtOrErrorNegativeIndex() {
          Observable.empty()
              .elementAtOrError(-1);
      }
  
      @Test
      public void elementAtOrErrorNoElement() {
          Observable.empty()
              .elementAtOrError(0)
              .test()
              .assertNoValues()
              .assertError(NoSuchElementException.class);
      }
  
      @Test
      public void elementAtOrErrorOneElement() {
          Observable.just(1)
              .elementAtOrError(0)
              .test()
              .assertNoErrors()
              .assertValue(1);
      }
  
      @Test
      public void elementAtOrErrorMultipleElements() {
          Observable.just(1, 2, 3)
              .elementAtOrError(1)
              .test()
              .assertNoErrors()
              .assertValue(2);
      }
  
      @Test
      public void elementAtOrErrorInvalidIndex() {
          Observable.just(1, 2, 3)
              .elementAtOrError(3)
              .test()
              .assertNoValues()
              .assertError(NoSuchElementException.class);
      }
  
      @Test
      public void elementAtOrErrorError() {
          Observable.error(new RuntimeException("error"))
              .elementAtOrError(0)
              .test()
              .assertNoValues()
              .assertErrorMessage("error")
              .assertError(RuntimeException.class);
      }
  
      @Test
      public void elementAtIndex0OnEmptySource() {
          Observable.empty()
              .elementAt(0)
              .test()
              .assertResult();
      }
  
      @Test
      public void elementAtIndex0WithDefaultOnEmptySource() {
          Observable.empty()
              .elementAt(0, 5)
              .test()
              .assertResult(5);
      }
  
      @Test
      public void elementAtIndex1OnEmptySource() {
          Observable.empty()
              .elementAt(1)
              .test()
              .assertResult();
      }
  
      @Test
      public void elementAtIndex1WithDefaultOnEmptySource() {
          Observable.empty()
              .elementAt(1, 10)
              .test()
              .assertResult(10);
      }
  
      @Test
      public void elementAtOrErrorIndex1OnEmptySource() {
          Observable.empty()
              .elementAtOrError(1)
              .test()
              .assertFailure(NoSuchElementException.class);
      }
  
      @Test
      public void dispose() {
          TestHelper.checkDisposed(PublishSubject.create().elementAt(0).toObservable());
          TestHelper.checkDisposed(PublishSubject.create().elementAt(0));
  
          TestHelper.checkDisposed(PublishSubject.create().elementAt(0, 1).toObservable());
          TestHelper.checkDisposed(PublishSubject.create().elementAt(0, 1));
      }
  
      @Test
      public void doubleOnSubscribe() {
          TestHelper.checkDoubleOnSubscribeObservable(new Function<Observable<Object>, ObservableSource<Object>>() {
              @Override
              public ObservableSource<Object> apply(Observable<Object> o) throws Exception {
                  return o.elementAt(0).toObservable();
              }
          });
  
          TestHelper.checkDoubleOnSubscribeObservableToMaybe(new Function<Observable<Object>, MaybeSource<Object>>() {
              @Override
              public MaybeSource<Object> apply(Observable<Object> o) throws Exception {
                  return o.elementAt(0);
              }
          });
  
          TestHelper.checkDoubleOnSubscribeObservableToSingle(new Function<Observable<Object>, SingleSource<Object>>() {
              @Override
              public SingleSource<Object> apply(Observable<Object> o) throws Exception {
                  return o.elementAt(0, 1);
              }
          });
      }
  
      @Test
      public void elementAtIndex1WithDefaultOnEmptySourceObservable() {
          Observable.empty()
              .elementAt(1, 10)
              .toObservable()
              .test()
              .assertResult(10);
      }
  
      @Test
      public void errorObservable() {
          Observable.error(new TestException())
              .elementAt(1, 10)
              .toObservable()
              .test()
              .assertFailure(TestException.class);
      }
  
      @Test
      public void badSourceObservable() {
          List<Throwable> errors = TestCommonHelper.trackPluginErrors();
          try {
              new Observable<Integer>() {
                  @Override
                  protected void subscribeActual(Observer<? super Integer> observer) {
                      observer.onSubscribe(Disposables.empty());
  
                      observer.onNext(1);
                      observer.onNext(2);
                      observer.onError(new TestException());
                      observer.onComplete();
                  }
              }
              .elementAt(0)
              .toObservable()
              .test()
              .assertResult(1);
  
              TestCommonHelper.assertUndeliverable(errors, 0, TestException.class);
          } finally {
              RxJavaCommonPlugins.reset();
          }
      }
  
      @Test
      public void badSource() {
          List<Throwable> errors = TestCommonHelper.trackPluginErrors();
          try {
              new Observable<Integer>() {
                  @Override
                  protected void subscribeActual(Observer<? super Integer> observer) {
                      observer.onSubscribe(Disposables.empty());
  
                      observer.onNext(1);
                      observer.onNext(2);
                      observer.onError(new TestException());
                      observer.onComplete();
                  }
              }
              .elementAt(0)
              .test()
              .assertResult(1);
  
              TestCommonHelper.assertUndeliverable(errors, 0, TestException.class);
          } finally {
              RxJavaCommonPlugins.reset();
          }
      }
  
      @Test
      public void badSource2() {
          List<Throwable> errors = TestCommonHelper.trackPluginErrors();
          try {
              new Observable<Integer>() {
                  @Override
                  protected void subscribeActual(Observer<? super Integer> observer) {
                      observer.onSubscribe(Disposables.empty());
  
                      observer.onNext(1);
                      observer.onNext(2);
                      observer.onError(new TestException());
                      observer.onComplete();
                  }
              }
              .elementAt(0, 1)
              .test()
              .assertResult(1);
  
              TestCommonHelper.assertUndeliverable(errors, 0, TestException.class);
          } finally {
              RxJavaCommonPlugins.reset();
          }
      }
  }
  